Portable sander and polisher



July 26, 1932. A. H. Roos 1,868,507

PORTABLE SANDER AND POLISHER Filed Jan. 25, 1930 3 Sheets-Sheet lINVENTOR 24 ATTORNEY .July 26, 1932. A H, ROQS 1,868,507

PORTABLE SANDER AND POLISHER Filed Jan. 25, 1950 3 Sheets-Sheet 2INVENTOR A.HR00S www@ ATTORNEY July 26, 1932. A H, R005 1,868,507

PORTABLE SANDER AND POLISHER Filed Jan. 25, 1950 5 Sheets-Sheet 3INVENTOR -HRUOS ATTORN EY Patented July 26, 1932 UNITED STATES PATENToFFicE AXEL H. ROOS, F CHICO, CALIFORNIA, ASSIGNOR T0 A. FREED, OF BANFRANCISCO, CALIFORNIA., TRUSTEE PORTABLE SANDER AND POLIS-H'EBApplication med January 25, 1930. Serial No. 423,3a5.

This invention relates to sanding and p olishing machines of thatcharacter in which the sanding or rubbing member is reciprocated througha certain distance by means of an electric motor mounted on thesupporting frame of the machine,l so-that the only Work the operator hasto do is to guide the movement of the machine over the surface beingworked on. The principal objects of my invention are to provide amachine of this4 general character having a pair of sanding or rubbingblocks reciprocatingtogether in such synchronized relation to each otherthat vibration is reduced to a negligible minimum and the operation ofthe machine is very steady; one

in which said blocks are so mounted that they may follow the contours ofcurved surfaces, so that the machine is very useful for rubbing down thefinish on automobiles and bodies of similar surface'configuration; andone in which the dust as raised rom'the surface being sanded isimmediately blown away while at the same time the mot-or is kept cool.

As further objects I have provided a novel clamping means for holdingthe sanding pads in place o n the reciprocating blocks; a means lforenabling moisture to be blown onto the surface being operated on; andarranged the machine so that a centrifugl or rotary rubbing or polishingdisc may easily mounted on the machine and driven by the motor thereofwhen it is desired to use a device of this character instead of thereciprocating elements.

The device is also so constructed as to be fool-proof', as there are noadjustments to be madeat any time. I l' These objects I accomplish bymea-ns of such structure and relative arrangement of parts as will fullyappear by a perusal of the following specification and claims.

In the drawings similar characters of reference indicate correspondingparts in the several views.

Fig. 1 is a side elevation of my improvedv machine as operating onafcurved surface.

Fig. 2 is a similar view somewhat enlarged and mainly in section.

I Fi 3.

substantially ig. 4 is a perspective view of a special 55 clampreleasing tool.

Fig. 5is aside elevation of the machine (sliown as equippedwith a rotarypolishing isc.

Fig. 6 is a similar view showing the machine e u ipped with a waterspray tank. Fig. is a perspective view of a pad holding rame adaptedfor'detachable engagement with the reciprocating blocks. v

Referring now more particularly to the characters of reference on thedrawings the numeral 1 denotes the supporting body of the machine-ametal casting of substantially rectangular form. Superimposed on andcovering the body is a cap 2 which forms an enclosed chamber 3 with thetop ofthe body. flhis cap forms part of an enclosing housing 4 for anelectric motor 5 set on a vertical axis and disposed centrally of thelength 7 of the cap and body. A vertical control handle 6 for themachine extends between the top of the housing and one end of the capand has vthe motor switch 7 mounted thereon in a convenient location.Another 'knob-like handle 6a is mounted on the opposite end of the cap.Current for the motor is obtained through a flexible extension -cable 8which projects the necessary distance fromthe top of the motor and isadapted for detachable connection with an outlet of standard form.

The motor shaft 9 below the motor is journaled in a ball bearing 10mounted inthe bottom housing portion of the cap and projects into thechamber 3, being there connected to a spiral pinion 11. This pinionmeshes' with opposed speed reducing gears 12 which mesh with other andlarger gears 13 mounted in opposed relation to each other adjacent theopposite endsl of the body. All these gears and their bearings aremounted in the enclosure 3 and may thus be easily kept in a properlylubricated condition. Also the bearings are protected by felt packings,so 100 that no grease canget out, and no dirt can get in. Theshafts 14of the gears 13 are journaled in suitable bearings in the body and capand project downwardly through the body for axial driving connectionwith discs 15 disposed in circular recesses provided in said body. Pins16 are fixed in and depend from 'these discs in cranked relation to theaxial shafts. 0n theirv lower ends these pins carry rollers 17 riding inslots 18 cut transversely in the upper surfaces of carriages 19. Thesecarriages are slidably supported in a suitable manner from tracks 20rovided along the sides of the body at the ottom. The rotation of thegears therefore causes the carriages to' be reciprocated; the discsbeing set so that the pins thereof will he in opposed relation to eachother,

.or so that the carriages are at the opposite ends of their strokes atthe same time. The discs are therefore properly balanced 1n theirreciprocative movements and vibration of the machine as a whole isreduced to a minimum.

The carriages are provided with .depending side ears 21 disposedcentrally of their wit blocks 22, so that the lattercan swing ontransverse horizontal axes. Counteracting compressing springs 23 betweenthe blocks and carriages on both sides of the swivel connectionsnormally hold the blocks in horizontal positions. This swivel mountingof the blocks enables them tomove relativeto each other so that they maysubstantially follow the contour of a curved surface as shown in Fig. 1thus making the device of more universal service than Awould be the oaseif said blocks were rigid and permanentl horizontal or parallel to eachother. The ower portions 22a of these k-blocks are both wider and longerthan the upper portions 22. These'lower portions are flat on the bottomand are faced with cushions such as ads 24 of felt or the like, whichform bac ings for thev sanding or other work sheets 2 5.

Each sheet is bent up against the ends of the corresponding blockportion 22 and'is then folded back along the top of said block portion asufficient distance to extend "over transversely extending semicirculargrooves 26 cut in said top surface adjacent the ends of the block.Circular clamping brars l27 adapted to fit' in the grooves arev mountedin' connection withspring pressed supports 28 pivoted on the blocks,said supports having inverted hook shaped handles 29 to enable thesupports to be manipulated andthe bars raised against the resistance ofthel springs.

Since these handles are necessarily somewhat small and are also locatedin spaces of somewhat restricted size, I preferably provide a specialtool for manipulating the same to attain the releasevof theclampingbars. Th

length and' which have pivotal connection tool comprises alstraightshank 30 having a easily placed or removed in position on the Ysupporting block and is firmly'held against displacement by reason ofthe groove and clamping bar arrangement without danger of saidv sheet`becoming loosened by being torn by the clamping means.

To cool the motor I mount a fan 33 in a chamber 34 provided in the bodybetween the carriages, said fan chamber communicatying with the interiorof `the motor housing by means 'of side passages 35 which are keptseparate from the gear enclosing chamber 3, as shown in Fig. 3. I l

These passages in turn communicate with openings 36 in the top of themotor housin by means of vertically extending grooves 3 formed in andabout the housing outwardly ofor in surrounding relation to the motor.The fan is mounted on a direct extension 38 7of the motor shaft whichterminates lin a threaded portion depending some distance below the fanfor a purpose hereinafter seen. The bottom of the fan chamber is coveredby ya nozzle 39 which depends centrall between .the reciprocating blocksand is Jo substantially rectangular form .with its major axis extendingtransversely of the machine. By reason' of this fan arrangement lit willtherefore be seen that air to cool the motor is drawn down through thetop of the housing and is then discharged -through they nozzle 39directly against the surface being sanded; so that said'surface iskept'clear of the sanding dust as it accumulates, and such dust is keptfrom'being again Worked into the surface or from prematurely clogging upthe sanding sheets.

Should it be desired to utilize a centrifugal rubbing element instead ofthe reciprocating blocks, I provide an attachment which can be used forthis purpose. This attachment comprises a circular plate 40 having asuitable workvpad 41 secured to its under-surface, and a centrallydisposed stem 42 projecting upwardly therefrom and tapped onits up r endfor connection to the lower end of the fin shaft 38. To thus attach theshank to said ICI) shaft it is only necessary to remove the fan p nozzle39; thelength of the shank being such that the plate 40 is then belowthe reciprocating blocks a suicient distance to properly clear the same.

condition if desired. This attachment comprises a water tank 43 adaptedto be detachably secured onto the machine in any suitable manner as bystrapping thesame onto the motor housing, as shown in Fig. 6. Smallpipes 44 depend from the bottom of the tank and proj ect through the capso as to drip into the passages 35. A needle valve structure 45 ofordinary form controls the flow of water from the tank'into the pipes'44. By means of this arrangement it will beseen that as the water dripsinto said passages thel shaft revolving fan will' act on the drops ofwater and substantially vaporize the samesso that the air\ as blown ontothe surface being worked-on will be in' the form of a very fine spray.In order to utilize relatively thick polishing orrubbing pads in-connection with the reciprocating blocks, and which cannot be bent overto engage the clamping bars, I have provided a special supportifng meansfor such f pads, which is shown in Fig. 7. This means comprises a fiatplate 46 of substantially the same size as the bottom area of the blockportions 22a, and having depending gripping flanges 47 to engage thework pad 48. Spring clip members 49 upstand from the ends of the bodyfor directing an air/blast onto the surface engaged by the rubbing sheetand additional means mounted in connection with the body for injectingdrops of a liquid into the air blast.

2. A structure as in claim 1, with additional means mounted inconnection with the body for injecting drops of a liquid into the airblast ahead of the nozzle. l

3. A rubbing machine including a body, a

block to support a rubbing element movablymounted in connection with thebody, means to reciprocate said block mounted on the body, a driven fanmounted on the body and arranged in connection with air `passage meansto direct a blast of air against a surface engaged'by the rubbingelement and in the path of reciprocating movement of said element, andliquid passage meansdelivering into the air passage means ahead ofthefan.

In testimony whereof I ariix'ed my signature.

AXEL H. ROOS.

the plate and are adapted to project upward-y ly against andfrictionally engage the ends of the block members 22a. Relatively small'flanges 50 project upwardly from the plate at its sides to engage thesides of the block members 22a and thus prevent lateral displacement ofthe plate. j

By using a liquid wax in the tank 43 instead of water, and by replacingthe sanding sheets by rubbing pads, an ecient Waxing machine isprovided.

Should the motor stop when the crank pins 16 are in opposed dead centerrelation to each o other, they may be initially turned beyond suchrelationship by means of a knurled finger nut 51 fixed on and turnablewith the upper end of the motorshaft 9 above the houslng.

From the foregoing description it will be readily seen that I haveproduced such a device as substantial-ly fulfills the objects of theinvention as set forth herein.

While this specification sets forth in detail the presentandpreferred-construction of the device, still in practice suc-h deviationsfrom, such detail may be resorted to as do not form a departure from thespirit of the invention,

. as defined by the appended claims.

Having thus described my invention what i I claim as new and useful anddesire to secure by Letters Patent is:

